ABSTRACT
Introduction .................................................................................................................................. 169
Echinacea
Constituents................................................................................................................ 169
In Vitro
Pharmacological Characterization of
Echinacea
Constituents............................... 170 Summary ...................................................................................................................................... 175 References .................................................................................................................................... 178
The medicinal herb
Echinacea
is a popular herbal remedy, reputed to be an immunostimulant. Three primary species of
Echinacea
are commonly employed in commercial preparations:
Echinacea angustifolia
,
Echinacea purpurea
, and
Echinacea pallida
. While there is a growing body of scientific evidence that supports the marketed uses of
Echinacea
, a tremendous deficiency still exists in our understanding of its pharmacological properties and human health benefits. This results from the various processing techniques employed for different species and sections of the plant that are harvested (roots and/or aerial parts) and their final formulation as a tincture, tablets/capsules, or teas. In fact, final product forms range from simple preparations of dried root and herb powders, pressed juice, or extracts standardized to a small percentage of constituent marker compounds. To further complicate matters, clinical trial results have demonstrated limited success, probably due to the lack of pharmacological characterization of the study material.
